Detergent composition



United States Patent Ofice Patented Mar.-a7 1956 DETERGENT COMPOSITION Homer W. McCnne, Cincinnati, Ohio, r to The Procter & Gamble Company, Cincinnati, Ohio, a corporation of Ohio No Drawing. Application September 20, 1954, Serial No. 457,311

3 Claims. (Cl. 252-137) This invention relates to liquid detergents. More particularly it relates to liquid synthetic detergents that contain a large amount of a detergency builder so that they can be used to wash heavily soiled clothes. Such a detergent, which in the past has been available mainly in the solid form, is commonly known as a heavy-duty detergent.

There have been few attempts to develop a heavy-duty liquid detergent, because of the ditliculty of formulating a solution which contains adequate amounts of synthetic detergent, of detergency builder and of inhibitors of corrosion by the builder. The usual ionic inorganic detergency builders that are effective with synthetic detergents are corrosive to aluminum, consequently sodium silicate, which inhibits this corrosion, is desirably added to prevent this corrosion, and this creates a further difliculty, hereinafter described.

I have discovered that these several difliculties may be overcome by the use, in certain ranges of proportions, of synthetic detergents of certain kinds and a specific detergency builder, providing a combination having a unique ability to tolerate eifective concentrations and ratios.

To be sufliciently effective so that only a reasonable amount of the liquid detergent need be used in a washing machine, it is desirable that the concentration of active ingredient be about that of the heavy duty detergents in granule form, namely 17 to 25%. To be effective as an all purpose heavy-duty detergent, the builder is preferably used in amounts at least equal to that of the synthetic detergent. This is true even when the unusually efiective builder that I employ is used. If one were to attempt to make a solution of parts of synthetic detergent and 20 parts of an alkali metal phosphate, the phosphate would "salt out the synthetic organic detergent (in standing and the preparation would separate into two or more layers. For this reason I have selected sodium phytate as the builder. Sodium phytate, CeHeOaPsNau is the sodium salt of phytic acid (inosotol hexaphosphoric acid). The technical grade used in my compositions contains water and a small amount of calcium and magnesium (6% max.) but is otherwise practically the pure compound, asrepresented by the following structural formula.

Sodium phytate has two advantages: it is not very active as a salting out ingredient, and it has high activity as a detergency builder, so that less of itis required than of other commonly used detergency builders.

My invention comprises a liquid heavy duty synthetic detergent in which a specially chosen anionic sulfuric reaction product having high detergency is built with sodium phytate, rendered non-corrosive towards aluminum with sodium silicate, and brought to the proper viscosity with a pair of solubilizers.

To select the most promising synthetic detergent, I made preparations of synthetic detergent and sodium phytate containing the following amounts of each, the remainder to add up to parts in each case being water.

Detergent 5 parts, sodium phytate 30 parts.

Detergent 15 parts, sodium phytate 15 parts.

Detergent 15 parts, sodium phytate 30 parts.

A large number of synthetic detergents were tested in these compositions, including the alkyl benzene sulfonates, the taurides, and the alkyl sulfates.

Magnesium alkyl sulfate formed an insoluble magnesium phytate. The primary sodium alkyl sulfates formed a clearsingle phase solution with both builder and synthetic detergent in solution. All of the other detergents, tested with the accompanying phytate, gave two layers with at least two of the above three combinations tested.

Because other experiments indicated its relatively unsatisfactory detergency, the secondary sodium alkyl sulfate was rejected, and the sodium coconut alcohol sulfate was found to be the preferred choice for the synthetic detergent of my invention. Potassium alkyl sulfate is not soluble enough to be useful. I have determined that the upper limit of solubility at 77 F., as a single phase, where the builder is present in twice that of the sodium alkyl sulfate, is 30 parts sodium phytate and 15 parts of sodium alkyl sulfate; where the alkyl sulfate and phytate are in a 1:1 weight ratio, the limit is 22% parts of each.

Ionic builders containing phosphates corrode aluminum. Sodium phytate is almost as bad in this respect as the sodium phosphates, pyrophosphates and tripolyphosphates, so that it is necessary to add sodium silicate to the solution to prevent this corrosion. Fortunately sodium phytate is unique among ionic phosphate builders in that its concentrated solutions allows substantial amounts of silicate solids to remain in solution with sodium alkyl sulfate as will be shown in the specific examples. Ammonium alkyl sulfates, and ethanol amine alkyl sulfates in concentrations effective for my purpose will precipitate silicates from solution with or without sodium phytate.

Concentrated aqueous solutions containing sodium coconut alcohol sulfate, sodium phytate in substantial amounts, and sodium silicate are of high viscosity. A composition containing 20% alkyl sulfate .and 27.5% sodium phytate, for example, had a viscosity around 600,000 centipoises and a chill point of about 70 F. I have found, however, that both the viscosity and chill point may be reduced by the addition of a pair of solubilizers. Thus if 6% of the water is replaced by 3% of sodium octyl sulfate and 3% of ethylene glycol monobutyl ether, the viscosity is reduced from 600,000 centipoises to about 10,000 centipoises and the chill point from 70' F. to 50' F. From 2 to 4 percent of each of the solubilizers may be used to achieve these eflfects; both must be used, but not of necessity in equal amounts. The sodium octyl sulfate alone lowered neither the viscosity nor the chill point; the ethylene glycol monobutyl ether alone caused the solution to separate into two layers. It is obvious that variation in the composition of each member of the solubilizer pair may be made. Commercisl octyl cut of fatty alcohol may be substituted for the relatively pure octyl alcohol that was sulfated and neutralized in my examples below. The commercial octyl cut contains a small amount (about 295%) of Ce alcohol, a large amount (about 30%) of C alcohol and a small amount (about 1%) of Cr: alcohol and about 67% of octyl alcohol. The sodium alkyl sulfate solubilizer should consist essentially of sodium octyl sulfate.

The other member of the solubilizer pair, the ethylene glycol monoalkyl ether, may be varied slightly. Ethylene glycol monoethyl ether and ethylene glycol 'monoisopropyl ether are not effective nor is an ether with a six carbon compound attached to the ether linkage, but the monopropyl, monoamyl and monobutyl ethers of ethylene glycol are effective in combination with the low molecular weight sodium alkyl sulfate.

The following examples are illustrative of the compositions of my invention.

The sodium coconut alcohol sulfate used in all of the examples Was Duponol ME contaning high molecular alcohols of C10 to C14 carbons in the chain purified by extraction with alcohol and having the following analysis:

Percent Alcohol soluble 98.7 Alcohol insoluble 1.3 Petroleum ether extract on the alcohol soluble 1.3 Moisture 1.3

The sodium phytate was obtained from the Corn Products Co. and was dried at 105 C. The analysis was Percent Total PaO- 42.2 Inorganic Pa 1.6

4 that in the othermachine containing the standard detergent, equal concentrations being employed.

The liquid detergent of Example 1 was superior to the standard synthetic granule in sudsing and equal in detergency for the first three loads.

ExampleZ Sodium coconut alcohol sulfate 12 Sodium phytate l2. Coconut alcohol 1.70 Coconut monoethanolamide .69 Sodium silicate solids 3.84 Sodium octyl sulfate 3.00 Ethylene glycol monobutyl ether 3.00 Water to make 100 parts 63.71

This product had a chill point of approximately 60' F., and an approximate viscosity of 300 centipoises. Its detersive qualities per unit of volume were 86% of those of Example 1. I

The ethylene glycol monobutyl ether was laboratory Example 1 -This was made up as follows, all parts being by weight:

Sodium coconut alcohol sulfate 14. Sodium phytate 14 Coconut alcohols 1.96 Coconut monoethanolamide 0.84 Silicate (solids basis) 4.48 Sodium octyl sulfate 3.00 Ethylene glycol monobutyl ether 3.00 Water to make 100 parts 58.72

The approximate chill point was 60' F., and the approximate viscosity was 400 centipoises.

This liquid composition and a standard synthetic granule detergent were compared by washing successive loads of fabrics in separate washing machines, the washing solution in one machine containing the liquid detergent, and

This preparation had a chill point slightly below 60' F.' and an approximate viscosity of 400 centipoises. The detersive action was proportional to the sodium coconut alcohol content, about 70% of that of Example 1, per unit of volume.

In other experiments I have determined that as little as 8% of sodium alkyl sulfate may be used, and as much as 22%, and the phytate may be varied also from 8.40 22%. The sodium silicate solids may be varied item 2 6% to 5%.

In these examples the organic suds boosters, coconut alcohol and .coconutmonoethanolamide were used. These minor additives may be varied in amount from the quantifies stated in the examples, for instance, the coconut alcohol may be present in amount between 156% and 2% and the coconut monoethanolamide between 36% and 1%, or omitted entirely from the preparations without substantially affecting the detersive properties or the physical characteristics of the liquid detergents. All of the other ingredients are essential to the physical characteristics or to the performance in use of the liquid detergents.

It will be appreciated that the invention contemplates as optional the use of other additives and ingredients of such nature and in such amounts that the purpose of the instant invention is not thereby defeated.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

'1. A heavy-duty liquid synthetic detergent containing primary sodium alkyl sulfate, in which the alkyl radical has 10 to 14 carbon atoms, in amounts of 8 to 22% parts, sodium phytate in amounts of 8 to 22% parts, sodium silicate solids, 2% to 5 parts, sodium octyl sulfate, 2 to 4 parts, an ether of ethylene glycol selected from the group consisting of monopropyl ethylene glycol ether, monoamyl ethylene glycol ether and monobutyl ethylene glycol ether, 2 to 4 parts, all of these in a single phase solution in water to make parts.

2. The detergent of claim 1, in which the ethylene gllycol monoalkyl ether is ethylene glycol monobutyl et er.

3.A heavy duty liquid synthetic detergent containing primary sodium alkyl sulfate, in which the alkyl is 10 to 14 carbons in amounts of 8 to 22% parts; sodium phytate,

in amounts of 8 to 22% parts; sodium silicate solids 2% to 5 parts; sodium octyl sulfate 2 to 4 parts, ethylene References Cited in the tile of this patent UNITED STATES PATENTS Martin July 18, 1939 6 Thurman Jan. 27, 1942 Toone Apr. 13, 1943 Wassell Apr. 27, 1943 Richardson Aug. 28, 1945 Lind Mar. 12, 1946 Artz "Feb. 14, 1950 Cornell Mar. 7, 1950 

1. A HEAVY-DUTY LIQUID SYNTHETIC DETERGENT CONTAINING PRIMARY SODIUM ALKYL SULFATE, IN WHICH THE ALKYL RADICAL HAS 10 TO 14 CARBON ATOMS, IN AMOUNTS OF 8 TO 22 1/2 PARTS, SODIUM PHYTATE IN AMOUNTS OF 8 TO 22 1/2 PARTS, SODIUM SILICATE SOLIDS, 2 1/2 TO 5 PARTS, SODIUM OCTYL SULFATE, 2 TO 4 PARTS, AN ETHER OF ETHYLENE GLYCOL SELECTED FROM THE GROUP CONSISTING OF MONOPROPYL ETHYLENE GLYCOL ETHER, MONOAMYL ETHYLENE GLYCOL ETHER AND MONOBUTYL ETHYLENE GLYCOL ETHER, 2 TO 4 PARTS, ALL OF THESE IN A SINGLE PHASE SOLUTION IN WATER TO MAKE 100 PARTS. 